ARM: dts: imx8mm-verdin: dm-spl for pinctrl_usdhc1 node

Let pinctrl configuration for eMMC node (usdhc1) also be
accessible in SPL.

Signed-off-by: Igor Opaniuk <igor.opaniuk@toradex.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
diff --git a/arch/arm/dts/imx8mm-verdin-u-boot.dtsi b/arch/arm/dts/imx8mm-verdin-u-boot.dtsi
index d091577..e60b9fa 100644
--- a/arch/arm/dts/imx8mm-verdin-u-boot.dtsi
+++ b/arch/arm/dts/imx8mm-verdin-u-boot.dtsi
@@ -69,6 +69,10 @@
 	u-boot,dm-spl;
 };
 
+&pinctrl_usdhc1 {
+	u-boot,dm-spl;
+};
+
 &pinctrl_usdhc2 {
 	u-boot,dm-spl;
 };